2. IGBT inverter H bridge and High frequency transformer type：belong to the middle transition products of high frequency power supply. It is the newest technique. For less 200 kw dc power, high frequency power supply has the advantage of cost，cheaper price.

3. Second Schottky diodes is the most energy saving type. Relatively high frequency, with high technical content, high maintenance personnel requirements, the failure rate is higher than thyristor rectifier and diode.

But I can tell you if you want energy saving type,you can choice IGBT mode rectifier，the Efficiency is more than 93%. Because the rectifier has no transformer，so the body is small. Due to there are many integrated circuit plate in it，maybe it will go wrong after half a year.

If you want stable rectifier and you have no professional maintenance staff，I suggest you to choise SCR type rectifier. Enclosed please find our quotation. This type rectifier can run more than 10-20 years.